2013 /2014 xc70 - What is the factory recommended tyre size for car?

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Mon 30 Jan 2023 10:55
2013 /2014 xc70 - What is the factory recommended tyre size for car? - James Girdler

Hi, I have a 2013 but apparently the vin means it's 2014 model year, I need to know the recommendation for tire size as I have no original handbook. I want to fit 235/55/17 Michelin cross climate 2 it currently has Toyo open country at 235/65/17 but the tyre people said it could blow the diff if incorrect. Any advice greatly appreciate thanks

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Mon 30 Jan 2023 11:40
2013 /2014 xc70 - What is the factory recommended tyre size for car? - elekie&a/c doctor
As it’s 4 wheel drive , it’s important to keep to the correct sizes . There should be a sticker on the door pillar or fuel flap to show you the options.
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Mon 30 Jan 2023 11:51
2013 /2014 xc70 - What is the factory recommended tyre size for car? - John F

The sidewall height of the 65 profile tyre would be 15.3cm (65% of 23.5cm). Thus the diameter of the whole wheel would be 43.2cm (17") plus 2 x 15.3 = 73.8cm.

The 55 profile tyre works out at 69cm. This reduces the diameter by 4.8cm (3.5%) so the car would ride about an inch lower, and the speedo would read 3.5% fast, assuming my maths is correct and 65 is the OE profile.

I presume you are talking about the centre diff of a 4WD as I can't imagine anyone putting odd sized tyres on the same axle. Anyway, I hardly think a diff would find it difficult to cope with one axle turning 104 revolutions for every 100 revolutions of the other axle. After all, the sole purpose of a differential gear is to allow one driven wheel to turn at a different speed to the other - the clue is in the name!

Incidentally, I saved myself several hundred pounds by fitting slightly higher profile tyres than those 'recommended' to my Audi - the reverse of what you are proposing (all 4 tyres, obviously!).

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Mon 30 Jan 2023 12:49
2013 /2014 xc70 - What is the factory recommended tyre size for car? - RT

The sidewall height of the 65 profile tyre would be 15.3cm (65% of 23.5cm). Thus the diameter of the whole wheel would be 43.2cm (17") plus 2 x 15.3 = 73.8cm.

The 55 profile tyre works out at 69cm. This reduces the diameter by 4.8cm (3.5%) so the car would ride about an inch lower, and the speedo would read 3.5% fast, assuming my maths is correct and 65 is the OE profile.

I presume you are talking about the centre diff of a 4WD as I can't imagine anyone putting odd sized tyres on the same axle. Anyway, I hardly think a diff would find it difficult to cope with one axle turning 104 revolutions for every 100 revolutions of the other axle. After all, the sole purpose of a differential gear is to allow one driven wheel to turn at a different speed to the other - the clue is in the name!

Incidentally, I saved myself several hundred pounds by fitting slightly higher profile tyres than those 'recommended' to my Audi - the reverse of what you are proposing (all 4 tyres, obviously!).

Many "4wd" including the XC70 don't have a geared centre differential but a clutched centre transfer - it's the clutch, cycling on/off, which allows a variation in rotational speed between front and rear axles - definitely not good to run different tyre sizes as that'll just wear the transfer clutch prematurely.

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Mon 30 Jan 2023 13:08
2013 /2014 xc70 - What is the factory recommended tyre size for car? - Crickleymal

What RT says. My Sorento is very sensitive to mismatched front and rear tyres. I seem to recall someone on the Kia forum saying a three percent difference was enough to trip the transfer box into engaging the clutches and having had it happen to me it's an uncomfortable sensation on a dry dual carriageway.

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Mon 30 Jan 2023 13:15
2013 /2014 xc70 - What is the factory recommended tyre size for car? - John F

I presume you are talking about the centre diff of a 4WD as I can't imagine anyone putting odd sized tyres on the same axle. Anyway, I hardly think a diff would find it difficult to cope with one axle turning 104 revolutions for every 100 revolutions of the other axle. After all, the sole purpose of a differential gear is to allow one driven wheel to turn at a different speed to the other - the clue is in the name!

Many "4wd" including the XC70 don't have a geared centre differential but a clutched centre transfer - it's the clutch, cycling on/off, which allows a variation in rotational speed between front and rear axles - definitely not good to run different tyre sizes as that'll just wear the transfer clutch prematurely.

Thanks - I live and learn! I wonder how many owners of these particluar 4WDs realise the importance of keeping an eye on tyre wear and pressures to ensure the front and rear rolling diameters are the same. It seems only a 1/4" difference might be enough to cause undue wear - and more expensive workshop activity.

www.transmissiondigest.com/how-things-work-four-wh.../

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Thu 9 Feb 2023 00:01
2013 /2014 xc70 - What is the factory recommended tyre size for car? - focussed

Hi, I have a 2013 but apparently the vin means it's 2014 model year, I need to know the recommendation for tire size as I have no original handbook. I want to fit 235/55/17 Michelin cross climate 2 it currently has Toyo open country at 235/65/17 but the tyre people said it could blow the diff if incorrect. Any advice greatly appreciate thanks

www.manualslib.com/manual/646793/Volvo-V70.html?pa...l

Note - I am assuming that this manual refers to a european spec car as the word "tyres" is not spelt "tires".

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